This invention relates to a flocculating clarifier of the type that has two drive arrangements, one for driving a sludge removal system at the base of the clarifier and the other for driving a stirring arrangement inside a flocculation well of the clarifier.
Flocculating clarifiers are well known to the prior art. In general, such clarifiers include a peripheral wall and base that together form a liquid containing volume. Solids containing influent is pumped into the clarifier, into an open bottom flocculation well mounted in a central upper portion of the clarifier. Solids or sludge which settle out of the influent are collected for removal from the base by means of one or more rotating arms. Clarified effluent is removed via an effluent conduit such as a weir.
In the past, two separate drive arrangements have been provided, one for the sludge collecting arms and the other for stirring blades of the flocculation well. Each drive arrangement has included its own speed reduction unit mounted at the level of the drive arrangement. When two drive arrangements are stacked in this manner, a number of problems are encountered. First, the overall height of the unit is relatively high, which can create an undesirably high minimum height for any cover. Second, the lower of the two speed reduction units may be difficult to reach for maintenance.
It is an object of this invention to provide an improved dual concentric drive arrangement for such a flocculating clarifier that minimizes overall height requirements while providing excellent maintenance access to both speed reduction units.